Low air pressure warning device



Patented Jan. 26, 1937 UNITED STATES PATENT OFFICE Application April 16,

2 Claims.

This invention is a device for completing a circuit through anelectrical signal of either the visual or audible type whereby toindicate low pressure in a pressure line of any suitable character.

The invention together with its objects and advantages will be bestunderstood from a study of the following description taken in connectionwith the accompanying drawing wherein:

Figure l is an elevational view illustrating the application of theinvention to a pressure line.

Figure 2 is an enlarged sectional view through the device takensubstantially on the line 2--2 of Figure 1.

Figure 3 is an exploded view of a cylinder and spring contact memberhereinafter more fully referred to.

Referring to the drawing by reference numerals it will be seen that 5indicates generally a pressure line through which water, air or the likeis forced under pressure.

In accordance with the present invention there is interposed in the line5 a casing 6 preferably of cylindrical form and provided at one end witha nipple 1 adapted to thread into a section of the line 5, and at arelatively opposite end with a screw cap 8 provided with a nipple 9adapted to be threaded into a second section of the line 5 as suggestedin Figure 1.

In the preferred embodiment thereof cap 8 has formed integral therewithand projecting inwardly therefrom a nipple III that has a threadedextremity on to which is screw-threaded one end of a cylinder I I ofbakelite, hard rubber or a any other suitable non-conductive material.

At the connected ends thereof nipple I0 and easing II are provided withregistering ports I2 as shown in Figure 2 so as to permit at all times aflow of fluid through the line to the end that the air gauge (not shown)with which such line is usually provided will register pressure at alltimes even though the pressure be below a predetermined amount, that isto say even though the pressure has fallen to such an extent as will, ina manner hereinafter more fully set out, permit a closing of the circuitthrough the electrically operable signal device.

A contact disk I4 of conductive material has a sliding fit within thecylinder II and is normally urged into engagement with the inner end ofthe nipple I0 which is also of conductive material through the medium ofa suitably provided and arranged coil spring I5.

Preferably spring I5 has its respective opposite ends anchored in anysuitable manner to 1936, Serial No. 74,771

the contact disk I 4 and caps I3 so that these parts may be handled as aunit.

The nipple IIJ together with the casing and associated parts is arrangedin an electrical circuit involving an electrically operable signal I6 5as suggested in Figure 1 which may be in the form of a bell, a light, orboth and which circuit is controlled by a main switch I'I, preferably.

As shown in Figure 1 the cap I3, contact disk I4 and spring I5 which areof conductive mate- 10 rial are electrically connected with one side ofthe battery 13 or other suitable source of electrical supply through themedium of a wire I8 that is connected at one end with a terminal bolt 20provided on and insulated from the closed end 15 of the casing 6.Secured to the bolt 20 is a conductor member 2| of metal or othersuitable material which at one end bears against the cap I3 as clearlyshown in Figure 2.

One side of the signal I6 is grounded while 20 the other side isconnected with the switch I I one side of which is also electricallyconnected through the medium of a wire 22 and terminal bolt 23 with thecasing Ii.

From the above it will be seen that when 25 there is a predeterminedpressure in the line 5 contact disk I4 will be normally held out ofengagement with the nipple I0 and against the action of spring I5.However, upon a fall of pressure spring I5 will force contact member I4into engagement with the threaded end of the nipple I I] thus completingthe circuit through the attachment (switch I! being closed) and theelectrically operable signal element I6 whereby the latter is actuatedfor giving a signal to the 35 end that one may be apprised of the factthat there has been a fall of pressure in the line 5.

As shown in Figure 1 casing 6 may be suitably provided as at 24 wherebythe same may be suitably anchored in position or attached to a sup- 40port as found desirable.

It is thought that a clear understanding of the construction, utilityand advantages of a device of this character will be had without a moredetailed description.

Having thus described the invention what is claimed as new is:

1. A signal circuit closure for disposition with a pressure line forclosing a circuit upon a fall of pressure in said line, and comprising acasing adapted to be disposed within the line, said casing being ofconductive material and adapted to be electrically connected to one sideof the signal circuit, said casing having a nipple extending inwardlythereof, a cylinder of non-conduc- 2 tive material connected with theinner end of said nipple, a contact member having a sliding fit Withinsaid cylinder, spring means engaged with said contact member and tendingto normally urge the same into engagement with said nipple forcompleting the signal circuit, and means for placing said contact memberin electrical connection with one side of the source of electricalenergy.

2. In a device of the character described a casing provided at one endwith an inlet nipple, and at its relatively opposite end with an outletnipple, said casing having internally thereof a nipple extendinginwardly from and in alignment with said inlet nipple, said casing andinternal nipple being formed of conductive material, a cylinder ofnon-conductive material threadedly engaged with one end of the internalnipple, a contact member having a sliding fit within said casing andadapted to move into engagement with said internal nipple for completingan electrical circuit, a cap of conductive material engaged with thefree end of said cylinder, a spring of conductive material connected atone end of said contact member and at a relatively opposite end with thefirst-named cap, a conductor member having an end engaged with thelast-named cap, and a terminal bolt securing the relatively opposite endof the conductor member to one end of said casing, said terminal boltbeing insulated from said casing.

HAROLD KRUSE.

